1. Field of the Invention
This invention relates to valve designs to reduce noise and erosion caused by flow through a valve.
2. Description of the Prior Art
High flow rates and pressures in flow control valves create noise problems and cavitation induced erosion damage. Cylindrical cages have been used in valves to reduce noise and cavitation induced erosion. These designs require that the sleeves be designed to fit a particular flow condition.
Valve trim designs to reduce cavitation are disclosed in ISA HANDBOOK OF CONTROL VALVES, 2d Ed, 1976 Instrument Society of America. Design criteria dictate that the pressure drop in the valve not exceed the vapor pressure of the fluid. The application of general valve design criteria to a specific valve appeared in an article entitled "Prudhoe Challenges New Choke-Valve Design" printed at page 92 of Oil & Gas Journal, Apr. 1, 1985.
Noise reduction has not been achieved to desired levels in valve designs which stress reduction of cavitation.